The other day I downloaded the official Android icons (http://developer.android.com/design/style/iconography.html#action-bar), but they weren't very easy to use in Sketch. So I decided to make a .sketch file to gather them all and distribute it. Hope you'll like it!
http://cl.ly/1P0P1s3S0F3d/download/android-icons-by-tristanremy.sketch.zip